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A032264
Number of ways to partition n labeled elements into pie slices of odd sizes allowing the pie to be turned over.
1
1, 1, 1, 2, 7, 23, 136, 872, 6952, 62813, 641536, 7277342, 90825472, 1236592403, 18239374336, 289719603812, 4930706056192, 89509486108793, 1726465695809536, 35259035421020282, 760088211047514112, 17247810060070731983, 410954011551070683136, 10257838886120978286752
OFFSET
0,4
LINKS
C. G. Bower, Transforms (2)
FORMULA
"DIJ" (bracelet, indistinct, labeled) transform of 1, 0, 1, 0, ... (odds).
E.g.f.: 1 + (g(x) + g(x)^2/2 - log(1-g(x)))/2 where g(x) = sinh(x). - Andrew Howroyd, Sep 12 2018
PROG
(PARI) seq(n)={my(p=sinh(x + O(x*x^n))); Vec(1 + serlaplace(p + p^2/2 - log(1-p))/2)} \\ Andrew Howroyd, Sep 12 2018
CROSSREFS
Sequence in context: A375130 A332802 A002494 * A139522 A163158 A355981
KEYWORD
nonn
EXTENSIONS
a(0)=1 prepended and terms a(21) and beyond from Andrew Howroyd, Sep 12 2018
STATUS
approved